For years, trick-or-treaters in Brooklyn’s Cobble Hill have been drawn to a street corner where an unconventional decoration goes up each Halloween: dozens of small carved pumpkins, impaled on an old iron fence and left to shrivel for weeks.

But this will be the last year for the ghoulish display at its current, off-the-beaten path location. Artist Jane Greengold is looking for a more public spot for the spooky work of art.

“She takes what seems like a simple thing anyone can do and she elevates it to a higher level,” said Dave Paco Abraham, vice president of the Cobble Hill Association.

Ms. Greengold began the project in 1999, when she lived at the stately red brick home at the corner of Kane Street and Strong Place. The professional artist—whose work includes a temporary display of lost and found objects for this year’s Grand Central Terminal centennial and a steel fence commissioned for a Queens firehouse—initially thought of the dozens of pumpkins simply as a fun art installation that she calls “Halloween Impalements.”

But after a few years, the display became a nearly annual neighborhood tradition (she missed two years). Even after Ms. Greengold moved to Fort Greene eight years ago, the home’s owner allowed her to continue the project, which draws onlookers who want to see how much the gourds have sagged and deformed day after day.

Jane Greengold

A view of the pumpkins on the fence in 2010.

“I have never done anything that got this much positive feedback,” said Ms. Greengold, who also works as a public interest lawyer for the New York Legal Assistance Group. “That’s kind of magnetic. It’s hard to stop.”

Always on the lookout for potential sites for her work, Ms. Greengold recalls looking at the sharp spikes on the long, rusty iron fence soon after moving to the home in 1997 and thinking: “This looks like a place where you could impale heads.”

After getting the pumpkins a few days before Halloween—too early and they might rot or squirrels will eat them—Ms. Greengold carves 40 or more, a time-consuming process since she tries to vary the features. The rest are done by family and friends.

Last year, she began soliciting carved pumpkins from the community for the fence’s 274 spikes.

Ms. Greengold is often joined by some of her four children and nine grandchildren in lighting the pumpkins with Christmas lights and distributing candy on Halloween.

How long the rotting little heads remain on the spikes—what she calls the “Dorian Gray” part of the project, referring to the lead character in the Oscar Wilde novel about how beauty fades—depends on the neighborhood’s enthusiasm and the weather. “I draw the line at Christmas,” she said.

Michelle Mannix, co-owner of nearby restaurant Ted & Honey, said Ms. Greengold’s work is a must-see for a neighborhood that treats Halloween “like New Orleans treats Mardi Gras.”

“Cobble Hill takes Halloween very seriously,” said Ms. Mannix.

Natalie Keyssar for The Wall Street Journal

Longtime Brooklyn resident Jane Greengold posed for a portrait by the fence on which she impales her carved pumpkins every year.

Ms. Greengold’s display encourages that spirit, she said. “People talk about going to it. It’s become a destination.…It’s too bad she’s not going to do it anymore.”

Ms. Greengold acknowledges that some people may view the pumpkins as a “neighborhood embellishment,” more of a seasonal decoration than an art installation. But, “when I do projects in the world, I think of them as art,” she said.

Now she’s ready to move the project into a less residential neighborhood and is eyeing a fence in a piece of land in Fort Greene, near where she lives and has her studio. She’s not sure what effect that will have on the popularity of the work, but she hopes it will still attract trick-or-treaters from all over.